In the pulp and paper industry the heart of the forming machine is the one or more foraminous belts by means of which the pulp is dewatered and on which a web is formed. These belts by which the machine is "clothed" may comprise synthetic fabric or woven bronze wire, depending on the particular machine involved, and its selected use.
In the particular case of twin wire machines, owing to the increased complexity of the forming path followed by the belts in passing over the rolls of the machine, and the diminished clearances existing within the machine between its various components, allied to the great widths of the machines and the difficulty in providing abundant aisle space at the front of the machine in which to carry out the fabric draping operation, the requirements for satisfactory draping are becoming more and more difficult to meet. The primary requirements are that the belt shall be installed rapidly, without damage and without ridging or wrinkling.
Prior arrangements, such as that of Canadian Pat. No. 438,586 -- Hornbostel, Dec. 17, 1946 and Canadian Pat. No. 874,194 -- Soomet et al., June 29, 1971 utilize rigidly supported arrangements having elaborate mounting means for supporting the belt in draped relation, and for laterally displacing the draping frame with the belt into the forming section. Such arrangements are space consuming and comparatively inflexible in their arrangement and use.